A new blood test, funded in part by the Movember Foundation, could predict which men with advanced prostate cancer will respond to new targeted treatments for the disease.
The test results would also mean that men who are unlikely to benefit from the drugs could be switched more quickly to alternative treatments, increasing their chances of survival, and helping to avoid the side effects of unnecessary treatment.
The test will have to be assessed in further trials but researchers say it costs less than £50 ($87 AUD).
Owen Sharp, Movember Foundation CEO: “This hugely promising test shows that life-saving and life-changing advances are within reach for men living with prostate cancer. When we can tailor a man’s treatment options based upon the specific biology of his disease the potential benefits are huge. This work is directly driven by the fundraising efforts of the Movember community who are making a huge difference to stopping men dying too young.”
Researchers have been able to detect tumour DNA in men’s blood and pick out cancers with multiple copies of the androgen receptor gene, which many prostate cancers rely on to grow.
Men with multiple copies of the gene responded much less well than otherwise to the targeted therapies abiraterone and enzalutamide – now standard treatment for advanced prostate cancer.
These men could be spared treatments that are unlikely to work for them, and doctors could offer them alternative options instead.
A team at The Institute of Cancer Research, London, and The Royal Marsden NHS Foundation Trust, along with colleagues in Europe, analysed blood samples from 265 men with advanced prostate cancer who were being treated with abiraterone or enzalutamide, either before or after docetaxel chemotherapy.
Researchers took samples from patients on three different clinical trials, both before receiving abiraterone or enzalutamide, and again after their disease began to progress.
In the primary trial of 171 patients, men in whom a blood test detected multiple copies of the gene that carries the instructions for making the androgen receptor were four times more likely to die over the course of the study than those who did not. The study included both patients who had previously received chemotherapy and those who did not.
The findings were confirmed in a second group of 94 patients where men with multiple copies had an eight-fold shorter response to treatment than men with one or two copies of the gene.
The androgen receptor is known to play an important role in helping cancers to become resistant to treatment with abiraterone and enzalutamide, which are standard treatments for men whose cancer is resistant to traditional hormone blocking therapy and has spread round the body.
The study is published today (Thursday 4th May) in the journal Annals of Oncology, and was funded by Prostate Cancer UK with support from the Movember Foundation, Cancer Research UK, and the NIHR Biomedical Research Centre at The Royal Marsden NHS Foundation Trust and The Institute of Cancer Research (ICR).
Dr Gerhardt Attard, Team Leader in the Centre for Evolution and Cancer at The Institute of Cancer Research, London, and Consultant Medical Oncologist at The Royal Marsden NHS Foundation Trust, leads this project:
“Abiraterone and enzalutamide are excellent treatments for advanced prostate cancer and some men can take these drugs for years without seeing a return of their cancer. But in other men, these drugs do not work well and the disease rapidly returns. Currently there is no approved test to help doctors choose whether these are the best treatments for an individual.
“We have developed a robust test that can be used in the clinic to pick out which men with advanced prostate cancer are likely to respond to abiraterone and enzalutamide, and which men might need alternative treatments.
“Our method costs less than £50, is quick to provide results, and can be implemented in hospital laboratories across the NHS. We are now looking to assess our test in prospective clinical trials and would hope it can become part of standard patient care.”